Re: Continuations

[Avi Bryant <address@hidden>]

On Mon, 11 Aug 2003, Scott McKay wrote:

> A binding is part of the state, right?  I argue that, in
> this domain, if you aren't explicitly capturing *all* the
> state so that it can be "persisted", or if you are not
> including tokens in your URLs (in links and in POSTs)
> that somehow identifies the state, then you have an
> incomplete design that will either:
>   - break in the face of load-balancing or crashed servers,
>   - or break in the face of the "Back" button

That's true; thus, if you're representing session state with
continuations, you must

a) use identifiying tokens in the URLs for the continuations
b) be able to persist the continuations and any associated state

Point (a) is trivial, and is done by (I'm sure) any of the
continuation-based web tools that have been mentioned.

Point (b) ranges from easy to nearly impossible depending (largely) on
what kind of a VM you are using; but that's an issue with particular
language implementations, not with the technique as a whole.